This invention relates to a vehicle suspension device, and particularly to such a device for use in the suspension system of a vehicle having a so-called active suspension system.
In European Patent Publi. No. 0114757 there is disclosed a wheeled land vehicle having an active suspension system including suspension devices in the form of hydraulic actuators by which the wheels (unsprung mass) of the vehicle are mounted to the body (sprung mass) of the vehicle. The suspension devices are controlled by signals representing heave, pitch, roll and warp modes of movement of the vehicle, possibly modified by signals representing the speed and lateral and longitudinal acceleration of the vehicle, to obtain a desired ride quality and attitude for the vehicle, the signals being derived from appropriate transducers located at appropriate positions on the vehicle.
In U.S. Pat. No. 4,761,022 there is disclosed a similar control system which also includes steering angle and yaw rate sensors on the vehicle, the signals from these sensors being used to control the steering characteristics of the vehicle.
Various such active suspension systems have been proposed, and a common feature of all known systems is that the necessary processing of the signals from the various transducers and the like around the vehicle is carried out centrally in a single common processing means such as a microprocessor, the signals from the transducers being transmitted to the processing means which in response thereto transmits control signals to the suspension devices to affect the necessary control thereof.